Copying the data to a temp table is still an option though you won't create a table as part of the script. After finding a set of records, you could use import data to copy that data to a table specified for your report. That might be a useful way to set this up if the same record might need to be listed in more than one found set.
Alternatively, the script could just use Import Records to copy over the Primary key and then a relationship can match the report records to the records in the original table.
And I'd use Replace field contents to set a field to a common value for each such found set so that I can sort on that field to group them in the report by keyword.
If a record cannot ever be part of more than one found set, you could just add a single field to update via replace field contents for grouping purposes on your current table. You may not want to do that, but it works and adding special purpose fields in FileMaker is often necessary.
Another alternative that may or may not work is to use Save Records as PDF to produce a PDF of your report. There's an append option with that script step that lets you append records to an existing PDF so you could perform a find for the first keyword, save as PDF, Perform a find for the next keyword, append its PDF to the first and so on... The main detail besides getting a PDF of the final report is that each appended PDF will start on a new page.